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When to plant in River Falls, WI

USDA Zone 4b

Everything below — frost dates, hardiness zone, and what to plant when in River Falls, Wisconsin — is derived from the closest NOAA station with complete climate normals.

In zone 4b, River Falls winters are severe; choose cold-hardy perennials and time annuals carefully around the frost dates above.

Station · RIVER FALLS · 1.3 km
Last spring frost
May 11
50% chance · 32°F
First fall frost
October 1
50% chance · 32°F
Growing season
143 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for River FallsA year-band showing 32°F frost risk from January to December for River Falls: last spring frost around May 11, first fall frost around October 1, about 143 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

RIVER FALLS · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are River Falls’s own odds, recorded at RIVER FALLS.

Frost-probability curves for River FallsProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around May 11 and the first fall frost around October 1, giving about 143 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FJun 6May 23May 6Sep 8Sep 24Oct 6
32°FMay 26May 11Apr 26Sep 19Oct 1Oct 15
28°FMay 16May 1Apr 16Sep 27Oct 11Oct 26

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19
Fall sowopen now
Broccoli
July 9July 23
Fall sowopen now
Cabbage
July 9July 23
Fall sowopen now
Carrot
July 9July 23
Fall sowopen now
Cauliflower
July 9July 23
Fall sowopen now
Napa Cabbage
July 9August 6
Fall sowin 4 days
Beet
July 23August 6
Fall sowin 4 days
Collards
July 23August 20
Fall sowin 4 days
Endive
July 23August 6
Fall sowin 4 days
Escarole
July 23August 6
Fall sowin 4 days
Fennel (Bulb)
July 23August 6
Fall sowin 4 days
Kale
July 23August 20
Fall sowin 4 days
Kohlrabi
July 23August 20
Fall sowin 4 days
Peas
July 23August 6
Fall sowin 4 days
Radicchio
July 23August 6
Fall sowin 4 days
Swiss Chard
July 23August 6
Fall sowin 4 days
Turnip
July 23August 20
Fall sowin 18 days
Arugula
August 6September 3
Fall sowin 18 days
Bok Choy
August 6August 20
Fall sowin 18 days
Chervil
August 6September 3
Fall sowin 18 days
Cilantro
August 6September 3
Fall sowin 18 days
Claytonia (Miner's Lettuce)
August 6September 3
Fall sowin 18 days
Corn Salad (Mâche)
August 6September 3
Fall sowin 18 days
Gai Lan (Chinese Broccoli)
August 6August 20
Fall sowin 18 days
Lettuce
August 6September 3
Fall sowin 18 days
Mizuna
August 6September 3
Fall sowin 18 days
Mustard Greens
August 6September 3
Fall sowin 18 days
Radish
August 6September 3
Fall sowin 18 days
Shungiku (Edible Chrysanthemum)
August 6August 20
Fall sowin 18 days
Spinach
August 6September 3
Fall sowin 18 days
Tatsoi
August 6September 3

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in River Falls, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 22 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

RIVER FALLS
Primary
1 km · 287 m elevation
SPRING
May 11
FALL
Oct 1
ELLSWORTH 1E
20 km · 314 m elevation
SPRING
May 13
FALL
Sep 29
BALDWIN
22 km · 335 m elevation
SPRING
May 6
FALL
Oct 2

River Falls planting FAQ

When is the last spring frost in River Falls, WI?

River Falls's average last spring frost falls near May 11 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.

When is the first fall frost in River Falls, WI?

Expect River Falls's first fall frost near October 1 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is River Falls in?

River Falls is in USDA hardiness zone 4b. In zone 4b, winters are cold — pick cold-hardy varieties and protect tender crops.

How long is the growing season in River Falls?

River Falls has about 143 frost-free days — a short growing season — between the average last spring frost (May 11) and first fall frost (October 1).

When should I plant tomatoes in River Falls?

For River Falls, sow tomatoes indoors about March 16–March 30 and move the seedlings out around May 18, after the last spring frost.

Planting reminders

Never miss a window in River Falls

An email when it’s time to start seeds, transplant, and sow — timed to River Falls’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at RIVER FALLS, 1 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in River Falls, WI — Frost Dates & Zone 4b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00477226. Retrieved from https://blissgarden.com/wisconsin/river-falls.
When to Plant in River Falls, WI — Frost Dates & Zone 4b — BlissGarden